Heat sink clip assembly

Abstract

A heat sink clip assembly for attaching a heat sink ( 10 ) to a CPU ( 60 ) mounted to a motherboard ( 50 ). The heat sink clip assembly includes two bolts ( 40 ), and two wire clips ( 30 ). Two screw holes ( 16 ) are defined in opposite side faces of the heat sink. Each bolt includes a pole ( 44 ), a head ( 42 ), and a threaded end ( 46 ). Each clip has a coiled portion ( 32 ), and two spring arms ( 34 ) extending from opposite ends of the coiled portion. The coiled portions of the clips are respectively placed over the poles of the bolts. The threaded ends of the bolts are screwed into the screw holes; thus, each clip is retained between the head of a corresponding bolt and a side face of the heat sink. A hook ( 36 ) is formed on each spring arm, for engaging in a corresponding through hole ( 52 ) of the motherboard.

What is claimed is:  
     
       1. A heat sink clip assembly for attaching a heat sink to an electronic device that is mounted to a motherboard, the heat sink clip assembly comprising: 
       a pair of bolts threadedly engage in opposite sides of the heat sink; and  
       a pair of wire clips, each of the clips comprising a coiled portion retained over a corresponding bolt, and two spring arms extending from opposite ends of the coiled portion to engage with the motherboard.  
     
     
       2. The heat sink clip assembly as described in  claim 1 , wherein each of the clips is integrally made from a single piece of spring steel wire. 
     
     
       3. The heat sink clip assembly as described in  claim 1 , wherein each of the clips provides an amount of pressing force according to a composition of the wire, a cross-sectional diameter of the wire, a diameter of the coiled portion, and an amount and concentration of coiling of the coiled portion. 
     
     
       4. The heat sink clip assembly as described in  claim 1 , wherein each of the spring arms of each of the clips extends generally perpendicularly relative to a central axis of the coiled portion. 
     
     
       5. The heat sink clip assembly as described in  claim 1 , wherein a hook is formed at a distal end of each of the spring arms, for engaging with the motherboard. 
     
     
       6. The heat sink clip assembly in accordance with  claim 1 , wherein the bolts each have a threaded end adapted to threadedly engage in a corresponding one of the opposite sides of the heat sink, a head and a pole between the head and the threaded end, the coiled portions of the clips being retained over the poles of the bolts, the heads of the bolts having a diameter larger than that of the poles. 
     
     
       7. A heat dissipating assembly comprising: 
       a motherboard;  
       an electronic device mounted on the motherboard;  
       a heat sink attached on the electronic device, a pair of screw holes being defined in opposite sides of the heat sink; and  
       a clip assembly comprising a pair of bolts respectively threadedly engaged in the screw holes of the heat sink, and a pair of wire clips respectively retained over the bolts, the wire clips having engaging means for engaging with the motherboard and thereby resiliently attaching the heat sink on the electronic device.  
     
     
       8. The heat dissipating assembly as described in  claim 7 , wherein each of the wire clips is integrally made of a single piece of spring steel wire, has a coiled portion retained over a corresponding bolt, and further has two spring arms extending from opposite ends of the coiled portion, the engaging means being formed on the spring arms. 
     
     
       9. The heat dissipating assembly as described in  claim 8 , wherein four through holes are defined in the motherboard around the electronic device, the engaging means comprising a hook formed at a distal end of each of the spring arms, each of the hooks being engaged in a corresponding through hole. 
     
     
       10. A method for dissipating heat from an electronic device on a printed circuit board which defines a plurality of holes near the electronic device, the method comprising the steps of: 
       providing a heat sink defining a pair of screw holes in opposite sides thereof;  
       providing a pair of bolts each having a pole, a head and a threaded end;  
       providing a pair of wire clips each having a coiled portion and two spring arms extending from opposite ends of the coiled portion;  
       placing the coiled portions of the wire clips over the poles of the bolts;  
       screwing the threaded ends of the bolts into the screw holes of the heat sink;  
       placing the heat sink on the electronic device and resiliently moving the spring arms of the wire clips to securely engage in the holes of the printed circuit board, whereby the bolts exert pressing force on the heat sink and make the heat sink intimately contact the electronic device.